Bedtime calculator
When should I go to sleep?
Tell us when you need to be up. We’ll suggest bedtimes that let you wake between sleep cycles, which many people find easier than waking in the middle of one.
Try to fall asleep at one of these times
To wake up at 07:00, aim to be in bed by one of these times. We’ve allowed about 15 minutes to fall asleep.
A general guide, not a rule. Sleep cycles average about 90 minutes but vary from person to person and night to night. Most adults need around 7 to 9 hours.
How it works
Counting in cycles, not hours.
Through the night you move through cycles of lighter and deeper sleep. Waking at the end of a cycle, when sleep is lighter, tends to feel less groggy.
The calculator adds or subtracts whole 90-minute cycles from your time, plus the minutes you usually take to drop off. It can’t know how your own night will go: that’s what the smart alarm in the app is for.
Good to know
More on routines and mornings in our sleep guides.
Is 90 minutes right for everyone?
No. It’s a commonly used average. Real cycles can be shorter or longer, and they change through the night, so the suggested times are a starting point you can adjust.
Which suggestion should I pick?
The highlighted options give 7.5 or 9 hours of sleep, which suits most adults. The shorter options are there for the nights when that isn’t possible.
Why does it ask how long I take to fall asleep?
Your first cycle starts when you fall asleep, not when you get into bed, so the calculator adds that time on.
I still wake up tired. What should I do?
Feeling tired often has many causes. If you regularly wake unrefreshed, snore loudly or struggle to sleep for weeks at a time, speak to a doctor. Nightjar isn’t a medical device and can’t diagnose sleep problems.
Let the app find the lighter moment for you.
Nightjar’s smart alarm listens for movement in your wake window and rings when you seem to be stirring.